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group (Fairon-Demaret 1996a). This Formation was
deposited onto a shallow epicontinental platform in
an alluvio-lagoonal context. Restricted marine or
emerging lagoonal ponds characterizes the Evieux
Formation palaeoenvironments that were thus
strictly neritic (Thorez et al. 2006). The palaeoflora
is very diverse: Stockmans (1948) collected and
named 25 different taxa, but currently only 14
species have been formally recognized (Fairon-
Demaret 1996a). The flora has been attributed to
the VCo palynozone (Thorez et al. 2006). The
northeast American outcrops are found in the
Hampshire Formation at Elkins (Rothwell et al.
1988) and in the Catskill Formation at Red Hill
(Cressler 2006). The occurrences at Elkins of coal
beds with roots and bioturbated zones beneath
suggest a continental environment deposited in a
fluvial to deltaic context (Scheckler 1986). Sedi-
mentation at Red Hill occurred in an upper alluvial
plain context (Diemer 1992). Elkins and Red
Hill localities have both been attributed to the VH
palynozone, suggesting an age slightly younger
than that of the Belgian deposits (Scheckler 1986;
Traverse 2003).
However, several correlation issues exist
between American and European sediments (Streel
& Marshall 2007). As palynofloras are continental
markers, but also distributed in marginal sea
where they can be sometimes calibrated by the con-
odont stratigraphy, intercontinental correlations
depend on the availability of that calibration.
Richardson & Ahmed (1988) suggest a delayed
first occurrence of the characteristic spores of the
Fig. 1. Biostratigraphical chart of Famennian miospore
zones (right-hand column). Note presence of dotted lines
at the base of the VH miospore biozone that express the
uncertainty of correlations. Left-hand column: the
absolute ages (Gradstein et al. 2004) (stratigraphical
chart modified from Thorez et al. 2006).
Fig. 2. Palaeogeographical distribution of Upper and Uppermost Devonian seed plant localities. 1, Condroz sandstones;
2, Elkins, Red Hill and Port Alleghany; 3, Taffs Well, Baggy Beds and Avon Gorge; 4, Kerry Head; and 5, Oese
(map modified from Scotese 1999).
